.\"	$OpenBSD: esp.4,v 1.12 2015/03/30 20:34:32 miod Exp $
.\"
.\" Copyright (c) 1998 The OpenBSD Project
.\" All rights reserved.
.\"
.\"
.Dd $Mdocdate: March 30 2015 $
.Dt ESP 4 sparc64
.Os
.Sh NAME
.Nm esp
.Nd ESP NCR 53c94 on-board or SBus SCSI interface
.Sh SYNOPSIS
.Cd "dma* at sbus?              " Pq "SBus SCSI"
.Cd "esp* at dma?               " Pq "two flavours"
.Cd "esp* at sbus?              " Pq "depending on model"
.Sh DESCRIPTION
The
.Nm
is an on-board or SBus SCSI controller based on the NCR 53c94 chip, found
on some
.Tn Sun
UltraSPARC workstations.
.Sh DEVICE FLAGS
.Bl -tag -width "Bits XX-XX" -compact
.It Bits 0-15
Disable disconnect/reselect for the corresponding target
.It Bits 16-31
Disable synchronous negotiation for target "[bit - 16]"
.El
.Pp
The
.Nm
device flags may be OR'd together to enable any combination of
the features listed above.
Targets 4 through 7 typically have disconnect/reselect enabled on the premise
that tape devices normally have one of these targets.
Tape devices should be allowed to disconnect for the SCSI bus to operate
acceptably.
.Sh SEE ALSO
.Xr cd 4 ,
.Xr ch 4 ,
.Xr intro 4 ,
.Xr sbus 4 ,
.Xr scsi 4 ,
.Xr sd 4 ,
.Xr st 4 ,
.Xr uk 4
.Sh HISTORY
.Ox
support for the
.Nm
first appeared in
.Ox 3.0 .
